Copper-zinc alloy

ABSTRACT

A copper-zinc alloy includes 56-65%, by weight, of Copper (Cu), 0.2-2.0%, by weight, of Tin (Sn) for improving tensile strength of Copper (Cu) and for strengthening the corrosion resistance of Zinc (Zn), 0.1-1.0%, by weight, of Aluminum (Al) for ameliorating the yielding and tensile strength and corrosion resistance of the alloy, 0.01-0.6%, by weight, of Nickel (Ni) for improving the yielding and the tensile strength and the resistance and the heat conductivity of the alloy, lower than 0.5%, by weight, of Ferrite (Fe), with the balance being Zinc (Zn) and inevitable impurities, the alloy also includes a secondary material, which is Phosphorus (p), Arsenic (As) or both for strengthening the corrosion resistance of the alloy.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related to the lead free Copper-Zinc alloy,which particularly focuses on decreasing the cost of lead freeCopper-Zinc alloy to prevent the Copper-Zinc alloy from polluting ourenvironment and improving mechanical ability.

2. Description of the Prior Art

Typical copper-zinc alloys comprise a number of materials, such as Iron(Fe), Aluminum (Al), Tin (Sn), Nickel (Ni), and unavoidable impuritiesfor increasing the corrosion resistance, strengthen tensile, or thelike.

For example, U.S. Pat. No. 4,990,309 to Miyafuji et al. discloses one ofthe typical high strength Copper-Nickel-Tin-Zinc-Aluminum alloyscontaining Nickel (Ni), Tin (Sn), Aluminum (Al), Manganese (Mg), Zinc(Zn), Chromium (Cr), the balance of copper and inevitable impurities.

The typical high strength Copper-Nickel-Tin-Zinc-Aluminum alloy containsa large amounts of the copper up to 80% in terms of weight. However, thecopper is an expensive material that may greatly increase the cost ofthe alloy and that may greatly decrease or reduce the competition of thealloy.

U.S. Pat. No. 5,658,401 to Gaag et al. discloses another typicalCopper-Zinc alloy for semi-finished products and articles which arehighly loaded and subjected to extreme wear especially synchronizingrings.

However, the typical Copper-Zinc alloy comprises the Lead (Pb) which istoxic may damage worker health during producing Copper-Lead-Zinc alloyand will also release toxicity into drinking water which will damagehuman health and pollute our environment.

U.S. Pat. No. 7,128,871 to Davitz discloses a further typicalsilver-colored, tarnish-resistant, corrosion-resistant alloy with lowpercentages of copper and zinc for jewelry items, tableware items,dental items or other items that should resist tarnishing or corrosionand which require a non-brittle alloy.

However, the typical silver-colored alloy includes a large amount orpercentage of the silver up to about 92-95% in terms of weight which isan expensive material that may greatly increase the cost of the alloyand that may greatly decrease or reduce the competition of the alloy.

The present invention has arisen to mitigate and/or obviate theafore-described disadvantages of the conventional copper-zinc alloys.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide aCopper-Zinc alloy to decrease amount of Copper material for decreasingthe cost of the Copper-Zinc alloy and without any lead engaged thereinfor preventing the copper-zinc alloy from polluting our environment ordamage human health.

In accordance with one aspect of the invention, there is provided acopper-zinc alloy comprising 56-65%, by weight, of Copper (Cu),0.2-2.0%, by weight, of Tin (Sn) to improve the tensile strength and thecorrosion resistance of Zinc (Zn), 0.1-1.0% by weight, of Aluminum (Al)to ameliorate yielding strength and the corrosion resistance of thealloy, 0.01-0.6%, by weight, of Nickel (Ni) to improve tensile strengthand the corrosion resistance of Zinc (Zn) and the heat conductivity ofthe alloy, lower than 0.5% by weight, of Iron (Fe), and selected atleast one element from Phosphorus (P) and Arsenic (As) which amountsrange from 0.02-0.25% and 0.01-0.2%. Combining both materials could notbe more than 0.35%, and the remaining percent, by weight, of Zinc (Zn)with inevitable impurities.

Further objectives and advantages of the present invention will becomeapparent from a careful reading of the detailed description providedherein below, with appropriate reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A Copper-Zinc alloy in accordance with the present invention primarilycomprises a Copper material (Cu), which is composed of 56 to 65 percentin terms of weight that is relatively lower than that contained in theother invention related to Lead Free Copper-Zinc alloys to decrease thecost of the Lead Free Copper-Zinc alloy, Tin (Sn), which is composed of0.2 to 2.0 percentage in terms of weight, may ameliorate the tensilestrength and also strengthen the corrosion resistance of alloy. However,when the amounts of Tin (Sn) increase, the relatively fragile or brittlematerial: CuZnSn will be generated and may influence the deformation ofthe alloy, but will improve the cutting characteristic to the alloy.

For example, when the amounts of Tin (Sn) is lower than 0.3 percentage,the cutting property of the alloy may not be improved, and when theamounts of Tin (Sn) is more than 0.8 percentage, the cutting propertyand the tensile strength of alloy may be improved and the characteristicof corrosion resistance may be gradually strengthened. When the amountsof Tin (Sn) is more than 2.0 percentage, the corrosion speed of zinc(Zn) is about 0.010 mm/Hr, the more Tin (Sn), the better the cuttingproperty of the alloy and the better the corrosion resistance of zinc(Zn). However, when too much Tin (Sn) is contained in the alloy, theductibility of the alloy will be decreased. Therefore, the best amountsof Tin (Sn) is 0.2-2.0 percentage in terms of weight.

The alloy also contains Aluminum (Al), which is 0.1-1.0 percentage, byweight, that could improve the yielding strength and the corrosionresistance of the alloy. However, it may slightly weaken the ductibilityof the alloy. Too much percentage of Aluminum (Al) may decrease thestretchability of the alloy. In addition, the specific gravity ofAluminum (Al) is relatively lighter than specific gravity of the otherCopper-Zinc alloy. Adding a specific amount of Aluminum (Al) mayrelatively decrease weight of alloy. Both Aluminum (Al) and Tin (Sn)could improve the cutting property of the alloy.

The alloy also may comprise Iron (Fe) which could be well mixed theparticle of the alloy. However, Iron (Fe) which contain too much insidealloy may weaken the property of corrosion resistance. Therefore, alloycould not contain too much percentage of Iron (Fe) therein. And theamount of Iron (Fe) is preferably no more than 0.5%, in terms of weight.The alloy may further comprise unavoidable impurities therein.

The alloy which comprises Nickel (Ni) which may even particle of thealloy, strengthen yielding strength, tensile strength, corrosionresistance and heat conductivity of the alloy. Besides, themicrostructure which is composed of Nickel will be more uniform afterheating or extruding. The percentage of Nickel ranged preferably between0.01 to 0.6 percentages, in terms of weight.

The remaining balance of the alloy is Zinc (Zn), which may remarkablyweaken heating conductivity and electric conductivity. However, composedof Zinc could improve yielding strength. When contained amount of Zinc(Zn) is more than 20%, the corrosion may be occurred in humidenvironment or in sea, particularly when the environment containsAmmonia (NH₃). The cutting effect of the alloy will be improved when thepercentage of Zinc (Zn) is more than 33%. Too much zinc (Zn) maydecrease the malleability of the alloy. More than 45% of Zinc containedin alloy will be no economic value. In this invention, to solvecorrosion problem is to increase composition of Nickel, Aluminum and Tininstead of decreasing composition of Zinc.

Further, the alloy will comprise at least one of other materials, whichcould be Phosphorus (P) or Arsenic (As) or both. Combining with bothmaterials will be no more than 0.35%. The alloy which is composed ofPhosphorus (P) or Arsenic (As) could strengthen the corrosionresistance. The more Phosphorus (P) and Arsenic (As) are, the bettercorrosion resistance of the alloy is.

Phosphorus (P) could be used as deoxidizer and mend the flowing ofmelting Copper (Cu) and may improve the characteristic of welding, thecorrosion resistance and the anti-softness of the alloy. However addingPhosphorus (P) will weaken the heat conductivity and the electricconductivity of the alloy. In additional, an excess of Phosphorus maygenerate the fragile or brittle characteristic to the alloy, such thatthe amount of Phosphorus (P) is preferably ranged between 0.03-0.25% interms of weight.

Arsenic (As) may be suitably melted in copper (Cu), but may greatlydecrease the heat conductivity and the electric conductivity of thealloy, and Arsenic (As) may strengthen the corrosion resistance of thealloy, but will weaken the electric potential of copper (Cu). Suchmaterial which contains in alloy is preferably ranged between 0.01-0.2%,in terms of weight.

Accordingly, the Copper-Zinc alloy in accordance with the presentinvention includes a decreased amount of copper material for decreasingthe cost of the Copper-Zinc alloy and including no lead engaged thereinfor preventing the copper-zinc alloy from polluting our environment.

Although this invention has been described with a certain degree ofparticularity, it is to be understood that the present disclosure hasbeen made by way of example only and that numerous changes in thedetailed construction and the combination and arrangement of parts maybe resorted to without departing from the spirit and scope of theinvention as hereinafter claimed.

1. A copper-zinc alloy comprising: 56-65%, by weight, of Copper (Cu),0.2-2.0%, by weight, of Tin (Sn), 0.1-1.0%, by weight, of Aluminum (Al),0.01-0.6%, by weight, of Nickel (Ni), lower than 0.5%, by weight, ofIron (Fe), and at least one element selected from Phosphorus (P) andArsenic (As), which are 0.03-0.25%, by weight, of Phosphorus (P),0.01-0.2%, by weight, of Arsenic (As), combining both materials being nomore than 0.35%, with the balance being Zinc (Zn) and inevitableimpurities.